1. Field of the Invention
The present invention relates to a display and a method of and a drive circuit for driving the display, more particularly to a liquid crystal display (LCD) and a method of and a drive circuit for driving the same.
2. Description of the Related Art
Recently, thin displays are widely used not only for notebook-type personal computers and notebook-type word processors, but also for normal- and wide-screen television units. It is required to provide a display capable of displaying images of different sizes.
Namely, recent computers and video equipment provide fine, high-quality images, and displays such as LCDs are required to display such images and images of different sizes.
To display fine, high-quality images, a display, for example, a matrix LCD must have many pixels. A color image of 640xc3x97480 dots requires 640xc3x97480xc3x973 (for red, green, and blue) pixels, and a color image of 1024xc3x97768 dots requires 1024xc3x97768xc3x973 pixels. An LCD designed for 640xc3x97480-dot images is improper to display 1024xc3x97768-dot images, and an LCD designed for 1024xc3x97768-dot images is improper to display 640xc3x97480-dot images.
Another requirement for LCDs is to display normal television images of 3:4 in aspect ratio as well as wide television images of 9:16 in aspect ratio. Further, improvements in multimedia technology ask one LCD to display images of various sizes.
The problems of the prior art will be explained later in detail with reference to the accompanying drawings.
An object of the present invention is to provide a display capable of properly displaying images of various sizes.
According to the present invention, there is provided a display comprising a display panel having a first aspect ratio, capable of displaying an image of a second aspect ratio whose width element is larger than that of the first aspect ratio; a gate driver for sequentially selecting gate lines of the display panel; a data driver for storing display data for one gate line and supplying the display data to one of the gate lines selected by the gate driver; and a timing controller for supplying control signals to the gate driver and the data driver so that predetermined data is displayed in top and bottom non-image areas of the display panel during a vertical blanking period.
A frequency of a clock signal used to sequentially select the gate lines may be increased during the vertical blanking period from a value for usual display data to a value for the predetermined data. A frequency of the clock signal for the predetermined data may be about two to four times higher than a frequency for usual display data. The timing controller may write the predetermined data simultaneously to the top and bottom non-image areas of the display panel during the vertical blanking period with the frequency of the clock signal being set to a low value. The timing controller may write the predetermined data to the data driver during the vertical blanking period in one latch operation. The first aspect ratio may be 3:4 corresponding to a normal-size image, and the second aspect ratio may be 9:16 corresponding to a wide-size image.
The display may further comprise an RGB driver for controlling red, green, and blue. The predetermined data may correspond to black. The display may be a liquid crystal display.
Further, according to the present invention, there is provided a display comprising a display panel of a first aspect ratio, capable of displaying an image of a second aspect ratio whose height element is larger than that of the first aspect ratio; a gate driver for sequentially selecting gate lines of the display panel; a data driver for storing display data for one gate line and supplying the stored display data to one of the gate lines selected by the gate driver; and a timing controller for supplying control signals to the gate driver and the data driver so that predetermined data is displayed in left and right non-image areas of the display panel during a horizontal blanking period.
The first aspect ratio may be 9:16 corresponding to a wide-size image and the second aspect ratio may be 3:4 corresponding to a normal-size image. The timing controller may write the predetermined data simultaneously to the left and right non-image areas of the display panel during the horizontal blanking period with the frequency of the clock signal being set to a low value. The timing controller may write the predetermined data simultaneously to the right non-image area of a given gate line and the left non-image area of the next gate line during the horizontal blanking period. The display may be capable of inverting an image according to data start signals.
Further, according to the present invention, there is provided a display comprising a display panel having a matrix of pixels, capable of displaying an image including a smaller number of dots than the number of pixels of the display panel; a gate driver for sequentially selecting gate lines of the display panel; a data driver for storing display data for one gate line and supplying the stored display data to one of the gate lines selected by the gate driver; and a timing controller for supplying control signals to the gate driver and the data driver so that gate lines having no image data are driven at intervals of several gate lines during a horizontal period and so that different ones of the gate lines having no image data are driven from frame to frame so that all gate lines are driven in several frames.
The gate driver may comprise a first and a second gate drivers arranged on each side of the display panel, to alternately drive the gate lines. The timing controller may have a clock generator for generating clock pulses having different frequencies and a clock controller for generating select signals to select one of the clock pulses as a gate shifting clock signal. The timing controller may drive the gate lines having no image data at intervals of several gate lines according to the first clock pulse selected by the select signal and may skip the remaining gate lines that are not driven according to the second clock pulse selected by the select signal, the period of the second clock pulse being shorter than that of the first clock pulse.
The polarity of a drive signal applied to the gate lines having no image data may be alternated whenever all gate lines are driven. The display may further comprise an image signal controller for controlling display data. The predetermined data may correspond to black.
According to the present invention, there is also provided a drive circuit of a display having a display panel of a first aspect ratio, capable of displaying an image of a second aspect ratio whose width element is larger than that of the first aspect ratio, a gate driver for sequentially selecting gate lines of the display panel, and a data driver for storing display data for one gate line and supplying the stored display data to one of the gate lines selected by the gate driver, comprising the function of supplying control signals to the gate driver and the data driver so that predetermined data is displayed in top and bottom non-image areas of the display panel during a vertical blanking period.
Further, according to the present invention, there is provided a drive circuit of a display having a display panel of a first aspect ratio, capable of displaying an image of a second aspect ratio whose height element is larger than that of the first aspect ratio, a gate driver for sequentially selecting gate lines of the display panel, and a data driver for storing display data for one gate line and supplying the stored display data to one of the gate lines selected by the gate driver, comprising the function of supplying control signals to the gate driver and the data driver so that predetermined data is displayed in left and right non-image areas of the display panel during a horizontal blanking period.
Further, according to the present invention, there is provided a drive circuit of a display having a display panel having a matrix of pixels, capable of displaying an image including a smaller number of dots than the number of pixels of the display panel, a gate driver for sequentially selecting gate lines of the display panel, and a data driver for storing display data for one gate line and supplying the stored display data to one of the gate lines selected by the gate driver, comprising the function of supplying control signals to the gate driver and the data driver so that gate lines having no image data are driven at intervals of several gate lines during a horizontal period and so that different ones of the gate lines having no image data are driven from frame to frame so that all gate lines are driven in several frames.
Further, according to the present invention, there is also provided a method of driving a display having a display panel of a first aspect ratio, to display on the display panel an image of a second aspect ratio whose width element is larger than that of the first aspect ratio, comprising the steps of writing predetermined data; and displaying the predetermined data written to the data driver in top and bottom non-image areas of the display panel during a vertical blanking period.
The method may further comprise the step of increasing, during the vertical blanking period, the frequency of a clock signal used to write display data from a value for usual display data to a value for the predetermined data. The frequency for the predetermined data may be about two to four times higher than the frequency for usual display data. The method may further comprise the step of writing the predetermined data simultaneously to the top and bottom non-image areas of the display panel during the vertical blanking period with the frequency of the clock signal being set to a low value.
The step of writing the predetermined data to a data driver during the vertical blanking period may be carried out in one latch operation.
In addition, according to the present invention, there is provided a method of driving a display having a display panel of a first aspect ratio, to display on the display panel an image of a second aspect ratio whose height element is larger than that of the first aspect ratio, comprising the steps of writing predetermined data; and displaying the predetermined data in left and right non-image areas of the display panel during a horizontal blanking period.
The method may further comprise the step of increasing, during the horizontal blanking period, the frequency of a clock signal used to write display data from a value for usual display data to a value for the predetermined data.
Further, according to the present invention, there is also provided a method of driving a display having a display panel having a matrix of pixels, to display on the display panel an image including a smaller number of dots than the number of pixels of the display panel, comprising the steps of driving gate lines having no image data at intervals of several gate lines during a horizontal period; and changing the gate lines having no image data to be driven from frame to frame so that all gate lines are driven in several frames.
The method may further comprise the steps of driving the gate lines having no image data at intervals of several gate lines according to a first clock pulse selected by a select signal; and skipping the remaining gate lines that are not driven, according to a second clock pulse selected by a select signal, the period of the second clock pulse being shorter than that of the first clock pulse. The method may further comprise the step of alternating the polarity of a drive signal applied to the gate lines having no image data whenever all gate lines are driven.